www/gitlab: Update from 8.16.8 to 8.16.9

Changelog: https://github.com/gitlabhq/gitlabhq/blob/v8.16.9/CHANGELOG.md

Also unbreak it by tighten the requirement of rubygem-rainbow
and relying at rubygem-google-api-client010 instead of updated
rubygem-google-api-client.

Reviewed by: remko, Matthias Fechner <idefix@fechner.net>